By Landau's theory the normal mass density(total density minus the superfluid mass density) is the total mass carried by excitations. For the BCS state and weakly interacting Bose gas the normal density is zero at zero temperature because there are no excitations. However in the presence of...
I am reading J.W.Negele and H.Orland's book "Quantum Many-Particle Systems". I don't know how one can derive equation (1.40) on page 6. The question is
For quantum many-body physics, suppose there are N particles. The hilbert space is
H_{N}=H\otimesH\otimes...H.
Its basis can be...
thanks for shawl, i am sorry that i forgot to post the book's name.the attached file is taken from "methods of theoretical physics, part 2" by Philip M. Morse and Herman Feshbach, on page 1362.
In studying the scattering problem, one should know green function in free space. while in two dimension, green function is the hankel function, seen in the attached file. bu i got confused in the second equation in the attached file. could anyone give me some details about this relationship? it...
GL's equation was first obtained from phenomenological consideration plus some symmetry constraints. Microscopic alculation can be performed by path-integral method in a more clearer way. Details are given in A.Altland and B.Simons book:"condensed matter field theory" on page286.
thanks. i am not at Cambridge. for your question, I don't know the answer. some one asked me this question long before. what i know is matsubara summation is nothing but a summation caused by Fourier transformation, like momentum.
hi, everyone,this is the first time i put a thread here.
thanks in advance
i am now learning functional integral techniques in condensed matter physics.when dealing with Matsubara frequency summations,one will meet with the convergency factor(for example...